This description relates to fluid piston-cylinders, and, more particularly, to a method and system for a fluid piston-cylinder assembly having an internal fluid reservoir.
Hydraulic power systems often use piston-cylinders to apply a linear force where needed. Typically, a piston-cylinder includes a cylindrically shaped body having a bore through a longitudinal axis of the body. One end of the cylinder is closed by a base end and a rod end is open to receive a piston and rod assembly. When a high pressure fluid, such as, hydraulic oil is introduced into the space between the base end and the piston, a force is imparted to the rod through the piston. The rod is generally coupled to a load, which is then manipulated by the force transmitted through the rod. The hydraulic oil is introduced through one or more hydraulic hoses or tubes connecting the space between the base end and the piston to a source of high pressure hydraulic oil, for example, a hydraulic pump coupled to a reservoir. Because the hydraulic pump may serve several loads, the hydraulic pump is often large and consequently positioned away from the loads. Also, because the loads are often in relatively less accessible locations, the hydraulic pump is located in a more accessible area, which is remote from the loads. Accordingly, to supply high pressure fluid to the space between the base end and the piston for each of the piston-cylinders associated with the loads, the piston-cylinders are connected to the hydraulic pump through long runs of hydraulic piping, tubing, and/or hoses. Over time, such piping, tubing, and hoses tend to develop leaks, which are an environmental concern and impact personnel safety.